A balloon is a flexible bag normally filled with a gas, such as helium, hydrogen or air. Some balloons are purely decorative, others are used for specific purposes. Early balloons were made of dried animal bladders. Modern balloons can be made from materials such as rubber, latex, chloroprene or a nylon fabric.
Balloons have a number of uses including for flight, in entertainment or as decoration and medical uses as well, for example, large balloons filled with hot air or buoyant gas have been used as flying machines since the 18th century.
Party balloons are mostly made of natural latex tapped from rubber trees and can be filled with air, helium, water, or any other suitable liquid or gas. The rubber allows for elasticity which makes the volume adjustable. Most of this rubber is made from recycled material, such as used vehicle tyres.
Filling with air is performed with the mouth, with a manual or electric inflator (such as a hand pump) or a source of compressed air.
Angioplasty is a surgical procedure in which very small balloons are inserted into blocked or partially blocked blood vessels near the heart. Once in place, the balloon can be inflated to clear or compress arterial plaque, and to stretch the walls of the vein. A small stent can be inserted in its place to keep the vessel open after the balloon's removal.
Certain catheters have balloons at their tip to keep them from slipping out, for example, the balloon of a Foley catheter is inflated when the catheter is inserted into the urinary bladder and to secure its position.
Regardless of their application, there have been many attempts in the art to provide a balloon or other inflatable article with self sealing action or characteristics. One example of an attempt to provide a self sealing toy balloon is taught in U.S. Pat. No. 2,625,770 which includes a pair of balloons, one located inside the other with the necks joined in a sealed relationship and with small passageways in the inner balloon for the escape of air therefrom into the outer balloon.
An example of a self sealing balloon for medical use is taught in U.S. Pat. No. 6,736,793. The balloon has an elastomeric membrane and a proximal opening with a self-sealing valve made up of a valve body for receiving an inflation instrument to inflate the balloon. The valve body is preferably formed of a biocompatible elastomeric material and includes a base portion and a sealing portion. The base portion is bonded to the elastomeric membrane so as to seal the proximal opening of the balloon. The sealing portion is located within the balloon and extends distally from the base into the balloon. The sealing portion is compressibly sealable in response to a pressure within the balloon following inflation of the balloon and removal of the inflation instrument.
There are also many examples of balloons or other inflatable articles that are provided with elaborate and complex valve arrangements which are positioned in the inlet of the balloon or other inflatable article during an assembly step either before use or during manufacture.
It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.